Vestibular migraine in low- and lower-middle-income countries: A scoping review.

Background: Vestibular migraine (VM) is a common cause of dizziness that is underrecognized, underdiagnosed, and challenging to effectively treat. The prevalence, appropriate diagnostic workup, and therapies for VM in low- and lower-middle-income countries (LLMICs) remain understudied. The objective of this scoping review is to evaluate the current state of VM research in LLMICs. Methods: PubMed, Embase, and Web of Science databases were searched to execute a scoping review of VM. Keywords "vestibular diseases" and "vertigo" were used in combination with terms referring to LLMICs as defined by the World Bank. Title and abstract screening, full-text review, and data collection were conducted by two authors independently. Results: Twenty-six studies were included in the scoping review. Most studies were cross-sectional (57.7%) or case studies/series (23.1%) and were conducted in urban settings only (92.3%). Geographic distribution of studies was skewed, with 65.4% of articles originating from India. The prevalence of VM among clinic patients ranged from 0.3% to 33.3%. VM most frequently presented as headache, nausea and vomiting, and photophobia. Radiographic imaging, audiometry, and electronystagmography/videonystagmography were the three most commonly utilized diagnostic modalities in the dizziness workup. The most studied pharmacotherapies included calcium channel blockers, followed by beta-blockers and antiepileptics. Case studies and series discussed less common VM pharmacotherapies, such as ayurvedic medicine. Conclusions: There is a need for more VM research in LLMICs, including innovative diagnostic approaches and therapies that can improve VM care globally. Equitable partnerships between LLMIC and high-income country researchers must expand vestibular research capacity and productivity in LLMICs.